War is a term that describes an armed conflict between opposing forces.

The cause of war can be attributed to a variety of factors. Some theories focus on innate biological or psychological factors and other theories center on social relations and institutions.

Optimists believe that wars are not unavoidable and may be avoided. Others are pessimistic about the preventability of war and believe that conflict is a natural process that must be accepted if we are to live in peace.

These types of theories divide into two schools, with one school focusing on the causes of war and the other focusing on the preventability of war. The former includes ethologists, psychologists, and psychoanalysts who focus on man’s innate drives (cf. Richard Dawkins), while the latter includes a wide array of scholars who posit that violence and war are products of human genetic evolution.

Some of these theories are based on a belief that humans have evolved into aggressive or territorial creatures, with others claiming that this is not true and that man’s innate drives can be channeled into more peaceful pursuits. Still others claim that human aggression is a natural process and that it will be sustained over time by evolution.

Other causes of war are based on the perception that humans are naturally driven by fear, honor, and interest. Thucydides posits that these factors persuade us to act beyond caution in times of tension and danger. Clausewitz argues that the desire for power is what motivates states to wage war. Geoffrey Blainey and Barbara Tuchman also argue that these motives are the fundamental drivers of wars.

In addition to the above, war can have a major effect on society and the environment. It can destroy infrastructures, ravage ecosystems and harm the health of the people who live in war-torn areas.

It can exacerbate political inequality, as well as create resentment and disenfranchisement within a nation or community. Citizens’ freedoms are curtailed and their societal and economic activities restricted.

Many of these effects are not immediately visible but can have long-term consequences. Among the most serious are shortages of water, food, medicine and energy; increased pollution and contamination; loss of life; and a decrease in quality of life.

There are also a number of psychological effects that can occur during and after a war, including the repression of speech, the deprivation of privacy and the suppression of individual desires. In some cases, war-related violence can lead to PTSD.

These and other effects can affect all aspects of a person’s life, both personally and professionally. They can impact their work, family and social life, education, and even their mental health.